Legitimizing property rights over the resources that participants use in dictator and ultimatum games has been shown to significantly alter behavior. However, a similar impact has not been observed in public good experiments. We employ an interior public good design with thirty periods of peer punishment, which allows groups to choose between plausible contribution norms without conflicting with efficiency. Across our Unearned and Earned treatments, endowments are randomly allocated or earned through a real effort task. In Unearned, both High and Low types adhere to a norm of contributing an equal proportion of one’s endowment. In contrast, in Earned, only Low types adhere to the proportional contribution norm, while High types contribute less than an equal proportion. Notably, deviations from the proportional contribution by High types are punished significantly less in Earned, suggesting a greater tolerance to such deviations when property rights are earned.
